Loading of sucrose from companion cells to sieve tube cell is:
Correct answer: B. Active transport
- A. Diffusion
- B. Active transport
- C. Passive transport
- D. Facilitated diffusion
Explanation
Loading of sucrose from companion cells to sieve tube cells involves active transport. Companion cells actively pump sucrose into the sieve tube elements of the phloem, creating a concentration gradient that drives the movement of sucrose from source tissues to sink tissues in the plant.
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